1997 7.3 Getting harder to start

[DougC]

1997 F-250, 7.3 liter, 78,0000 miles:

I know this is probably pretty basic, but it's my first diesel. Ambient temperatures around here are getting down to 30 F or so at night and around 45 F during the day. The truck is getting hard to start. Before the weather cooled down, it would start right up as soon as I turned the key after waiting for the "wait to start" light to go out. Now it takes three or four tries. It turns over fine. When it finally starts, it puts out white smoke that wasn't there before in the warmer weather. Once the engine is warm, there is little or no smoke of any color on start-up. What's the best way to diagnose so I don't go wasting money on unnecessary parts? Any tips would be greatly appreciated.

[Dietoremain]

GPR or glow plugs not working..

[tx_traveler]

I had the same problem when I owned a 1997 7.3. Replacing the heater relay solved the problem. The new relay was the one sold by NAPA.

[DougC]

Thanks. How do I test the relay? I think I found it on top of the engine on the passenger side near the fuel filter.

[DougC]

Found some tips from NCHornet. Followed testing procedure. Here's what I got:

Voltage at hot large terminal on relay is same as across battery.

Voltage at other large relay terminal with key on is 4.3 millivolts when it should be around 11 volts. Voltage at this same terminal with battery voltage across the two smaller relay terminals is .6 millivolts, next to nothing.

Relay does make clicking sound on and off.

Sounds like a bad relay. I'll read up on the Stancor.

Thanks for the tips and thanks to NCHornet for the write-up.

[PhL0aTeR]

i figured this was normal.... i just plug my block heater in at night.... i guess i should pull the multi-tester out!